Heat sink



FIG. 1 is a front perspective view of the heat sink of the present invention.

FIG. 2 is a back perspective view of the heat sink of the present invention.

FIG. 3 is a side view of the heat sink.

FIG. 4 is a side view of the heat sink, showing the opposite side from FIG. 2.

FIG. 5 is a top view of the heat sink.

FIG. 6 is a bottom view of the heat sink.

FIG. 7 is a front view of the heat sink; and,

FIG. 8 is a back view of the heat sink. 

CLAIM The ornamental design for a heat sink, as shown and described. 